Yesterday my buddie and I were able to play Gears 3 in co-op with me as the host. Later in the evening, this was not possible. He could join me in party chat, and I could join his co-op (not preferable because our progress is saved on my xbox), but whenever he responeded to my invites it would say unable to join the match. Also, I appeared in his friends list, but in the list of individual playing Gears my tag was greyed out and it said offline. Now, clearly I was not. And I was able to join some matches in wingman as a test. Any ideas?